Abstract
Adverse drug reactions (ADRs) are a major clinical problem. A rapidly growing body of evidence suggests that genetic factors, at least in part, determine individual susceptibility to ADRs. A large number of pharmacogenetic studies have identified a number of polymorphisms as predictors of drug efficacy and/or adverse events. These candidate markers should be investigated further to ascertain the underlying mechanism of action, for example, changes in the kinetic parameters of an enzyme, or transcriptional activity of a promoter region. In this chapter, we describe a transient transfection assay for the functional characterization of naturally occurring variants of UDP-glucuronosyltransferase (UGT) 1A1. This phase II drug metabolizing enzyme is involved in the glucuronidation of SN-38, an active metabolite of the anti-cancer drug irinotecan. Single-nucleotide polymorphisms of the UGT1A1 gene have been correlated to irinotecan-induced ADRs. Variant UGT1A1s are heterologously expressed in COS-1 cells and characterized in terms of the level of protein expression and enzyme kinetics.
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References
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© 2005 Humana Press Inc., Totowa, NJ
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Jinno, H., Hanioka, N., Tanaka-Kagawa, T., Saito, Y., Sawada, Ji., Ozawa, S. (2005). Transfection Assays With Allele-Specific Constructs. In: Innocenti, F. (eds) Pharmacogenomics. Methods in Molecular Biology™, vol 311. Humana Press. https://doi.org/10.1385/1-59259-957-5:019
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DOI: https://doi.org/10.1385/1-59259-957-5:019
Publisher Name: Humana Press
Print ISBN: 978-1-58829-440-1
Online ISBN: 978-1-59259-957-8
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